Every "aggressive driving" situation I have been in (autox, HPDE, etc) I have turned VTC/VDC off entirely. X-drive behaved normally, but there was no power cut.

For example: My first run at an autox course, I left stability controls on. There was minimal wheel slippage, but the traction controls pulled tons of power when there would have been traction loss. It felt like bogging a shift. However, on my next run, I turned everything off. On that run, wheel slippage was allowed, but the only response the car had was through redistributing the torque to either axle. I doubt that the car started out in RWD mode. But it wouldn't have mattered, since when I got the tiniest bit of oppo, x-drive interfered and sent power to the front.

TLR - x-drive cannot be turned off through any of the stability controls.

However, there are some individuals that are looking at a solution, right now